To allow an efficient and precise examination to find out whether desensitizing printing was performed correctly on a pressure-sensitive copy slip form.SOLUTION: Plural types of reference pressure-sensitive copy slip forms are prepared, are subjected to coloring
processing so that the region other than the desensitizing ink application region produces light, and are imaged. After that, an examination window is set in the gray-scale image of each reference pressure-sensitive copy slip form, the image part of the examination window is used as a
reference image part and is registered with the threshold value of the luminance that distinguishes the desensitizing ink application region and the other region in the
reference image part. Subsequently, an examination target pressure-sensitive copy slip form is subjected to coloring
processing and is imaged, an examination window common to the reference pressure-sensitive copy slip form for the gray-scale image of the examination target pressure-sensitive copy slip form is set, the image part in the examination window and its corresponding
reference image part are binarized, the difference between corresponding desensitizing ink application regions is taken, and it is determined that desensitizing print was performed correctly on the inspection target pressure-sensitive copy slip form when the difference is within an acceptance range.SELECTED DRAWING: Figure 1